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Why is VBAI slower on 8-Core Server than on Quad-Core Laptop?

When I run a particular inspection on my Quad-Core HP Laptop, it averages 1.7 seconds per inspection cycle, but running the same inspection on a Windows 2008 R2 Server Datacenter Edition, on an HP DL380 Reliance server, with all the memory I want and 8-Cores, the average inspection cycle is 4.7 seconds! 

 

I've replicated the issue on 3 separate servers, so its defineitely a systemic issue....but I'm at a loss to explain where the delay is.  Looking at the resource manager, both my laptop and the server use about the same number of threads (~150) for visonbuilder.exe

 

This particular inspection operates on stored images, pulling the images in, processing the image, and then saving (moving) the image to a "processed" folder, so there is a fair amount of file i/o but on my Laptop this file i/o only accounts for a fraction of the cycle time.  The images are on the same physical machine, but a separate VM (Drive) than VBAI.

 

Any ideas?

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Which version of VBAI / vision dlls are you using, and do you use a detect object that uses a Particle filter?

We fixed a problem with the particle filter function in Vision Development Module 2011 SP1, where the function that taking longer with more cores. This might the reason.

 

-Christophe

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I'm still on 2010, and I do use detect objects on my slowest routine....not sure what you mean by "particle filter", but I do filter for shape and size of objects found.  I have 2011 available, just waiting for a compelling reason to upgrade.....maybe this is it?

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If you do filter on the size and object found, it looks like this corresponds to the bug we fixed.

If you don't want to update to VBAI 2011 SP1, updating only the Vision Runtime Engine to 2011 SP1 should fix the issue.

You can download it from this link:

http://joule.ni.com/nidu/cds/view/p/id/2835/lang/en

 

Christophe

 

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We tried going from 8 cores to 4 on the server, and inspection times went from 4.7 seconds to 8....so apparently this is NOT my issue. 

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....on second thought.....after restoring to all 8 processors on the VM, cycle times went to 12 seconds!  Then, by changing the Affinity for VisionBuilder to 1 processor, I was able to get the cycle times down to 6 seconds again, still showing around 130 threads just as I did with 8 cores.....faster yes, but still slower than when I started!?  And my quad-core Laptop is running the same images in 1 second!   I guess we can try 2011 SP1.....but I'm at a loss to explain how the cycle times are varying so much.

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Please let us know the performance results you're getting with the 2011 SP1 dlls.

If they're still bad, would you mind sharing your inspection with NI, so we can investigate this slow down.

 

Thanks,

 

Christophe

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